Dobby chain



' Feb. 20, 1940. w. B. HARRIS 2,190,837

, nosey CHAIN I Filed Jan. 7, 1939.

II' I v boooooo b oo Sumter Wara B.7 7 Q' rrcb* I a f'i Q 4 n attorneyPatented Feb. 20, 1940 isms the BOBBY onam Warren E. HarriaMillbury;Mass. Application January 7; 1939, Serial No. 249.793

9 Claims. (oi. 1 9 334) of the pattern pegs. In order to attach thelinks thereto, it has been customary to bore holes, and

to pass straight pieces of wire therethrough, and shape their ends toform loops which attach to the links connecting with adjacent bars. Thatstructure has many disadvantages, owing particularly to the fact thatthe bar has been made wood. The pegs which determine the pattern of thecloth are made of iron slightly tapered and threaded with a coarsethread. The woodenbars are drilled with straight holes into which thesetapered metal pegs are inserted. When the peg is turned as a screw, thethread of the pin cuts a corresponding thread in the wooden bar and thusservesto hold the parts in place. This requires...that the wood becomparatively soft. Hence, if a peg is changed in position many times,this will wear the hole in the bar badly and thus require replacing the.bar with a new one; Moreover, the tapered peg threaded into anon-tapered hole tends to split the wooden bar and particularly wheninserted in the holes near the ends of the: bar which are most used. Thepeg may also be twisted in too tightly or not be in proper alignmentwith the hole and thus again injure the wooden bar. These wooden barsare expensive for many reasons, such as the necessity for a skilledworkman to pickout straight grained wood and avoid sticks having crossgrainswhich break easily. Moreover, there are many operations involvedin making these bars, including sawing the wood into slabs, shaping thesides by planer operations and cutting the beveled ends, drilling thepeg holes and the link holes, putting in the link wires and bending thesame. Any one of these may result in a defect which necessitatesthrowing away that particularpiece. Also, the link Wire must passthrough the bar in straight direction and not interfere with the holesin the bar or weaken the structure seriously. Hence, these Wires do notgive the maximum holding power and may slip in position, it beingparticularly desirable that they be not permitted to turn in the holesand thus throw the bars out of alignment. These, and

structions. I

It is aprimary object of my invention to over come such disadvantagesand to provide a dobby chain made of bars and links so constructed andarranged as to give the maximum of efficiency and service. Furtherobjects will be apparent in the following disclosure. t

In accordance with my invention, I propose to make the crossbar of amolded plastic material, and particularly a synthetic resin, having thedesired strength and other properties required and toattach it in thechain by linkagemembers which are positioned during themolding operationand maybe so shaped and arranged that they will be immovablyipositionedand will hold the bars properly as required.

Referring to the drawing which illustrates this invention: e Fig. l isan isometric View of a portion of a dobby chain, in which each cross barhas a single row of peg holes;

Fig. 2 is asection on the line 2-2 of Fig. 1;

Fig. 3 is a section on the line 3-3 of Fig. 1;

Fig. 4 shows one of the dobby pegs;

Fig. 5 is a topplan view of one of the pegs;

Fig. dis a detail showing a different form of chain link; 1

Fig. 7 is a modification showing a double row of dobloy peg holes and adifferent form of attaching link; and

Fig. 8 is a fragmentary View of a further modification showing anotherform of eyelet.

In this construction, thejcross bars are made of a plastic resinoid,such, as cellulose acetate, sold on the market under the trade name ofTenite, which is a synthetic moldable resin shape and which is capableof being used with the screw threaded dobby pegs to permit their readyremoval and insertion as required, I also, propose to form the dobby pegholes in this bar duringthe molding operation, and particularly,

to put the link attachment wires in position and to mold the plasticresin around these wires so as to hold them securely and permanently inplace without interfering with the use or the insertion and removal ofthe dobby pegs.

As shown in the drawing, the cross bar It] may be made in any suitableshape, but as illustrated, it is provided with beveled sides I! andbeveled ends it. Each bar is provided'with a single row i (Fig. 1) or adouble row (Figs. 6 and 7) of holes l4 therein which are so shaped andarranged as to hold the dobby pegs IS. The holes M are preferably madeslightly tapered, such as about 0.008 inch. The pegs l5, as shown inFigs. 4 and 5, are metal pins having substantially cylindrical ends l6and a flange I! which limits the inward movement of the peg andtherefore locates it'- relative to the bar. The peg is also providedwith a very. coarse screw thread l8, and this threaded end is taperedslightly and substantially to the same extent as is the hole M of thebar. Hence, when the dobby peg is inserted into the hole l4, it will fitcorrectly therein and may, because of its being slightly oversize, cut athread in the comparatively soft resinoid mate.- rial and. thus form itsown securing means. The holes l4 are so located and positioned that therequired number of pegs may be put in place, and it is intended thatthese pegs may be changed from one hole to another as required to governthe pattern of the cloth being woven on the loom.

The bar shown in Fig. 1 has but a single row of dobby peg holes whichare widely spaced shown in Figs. 6 and 7 which have two rows of holes.In the simplified form of Figs. 1 and 2, the attaching link wire may beshaped as a straight piece going through a hole in the bar and theopposite and projecting ends of each of the links may be bent to formloops 22 arranged to be connected by link 23 with loops of the link wireof adjacent bars. The ends of the wire are preferably bent back farenough so that they will be embedded in the resinoid substance of thebar and thus form closed eyelets from which the link 23 cannot escape.Since, the resinoid material of the bar is molded around the wire 20,the linkage will necessarily stay inposition. It is to be understoodthat these wires are suitably put in place in the mold, and the resinoidpowder is poured around the same and compressed by means of heat andpressure to the desired shape. The peg holes M are simultaneously formedby suitable cores located in the mold. Hence, the whole bar with itsassembled link-wires and peg holes may be formed inexpensively in asingle casting operation. I

The problem which has been met heretofore in connection with woodencross bars where double rows of staggered holes are used, is easilysolved by this construction, as shown in Figs. 8 and 7. Since a straightwire, shaped and ar ranged as shown in Fig. 1, would be close to adobby'peg hole and thus weaken the structure somewhat, I preferablyshape these connecting wires as shown in order to giveyariousadvantages. The wire of Fig. 6, has a bent central portion of a somewhatS-s'hape, so arranged and formed that it will not be close to any of theholes M; Also, the free ends of the wire are bent in opposite directionsto form the loops or eyelets 3| and 32 which are located substantiallyin alignment with the linkage eyelets of the other bars, as permitted bythe bent portion 3fl,'so that the tractive force of the linkage in Fig.6, the outer ends 3 of the wires may. also be substantially S-shaped, sothat each wire end lies at an angle to the normal tractiveforce.

Since the end is embedded in the bar, it interlocks with the resinoidmaterial and thus aids further in holding the wire linkage in place.That is, the bent portions 3%, 32 and 3 2 are all $-shaped and thesethree parts of the wire will each resist the lateral pull on the wireloop and hold the wire rigidly in position. In every case, the centersof the eyelets are in alignment with the direction of travel of thechain, and there is no tendency for the chainbars to twist out ofposition.

It will now be appreciated that since the bar is made of a moldedresinoid it may be easily shaped as desired, and that the holes may bemolded therein Without the expense of the drilling operations heretoforerequired for wooden bars. In particulanthe fastening wires which passthrough the bar may now be so shaped that they cannot pull out of placeor change in position and theyinterlcck with the resinoid and make astrong and rigid structure. The wooden bars have necessarily requiredthat the wire be straight throughout that portion lo cated within thebar; hence such a wire cannot be permanently locked in place butmaybecome loose. Moreover, the molded bar permits the use of a linkagewire, which is bent in any-desired shape, and the wire may be arrangedprior to the molding step in any location of maximum. advantage. Due tothe wire having a crooked central portion and its ends embedded in theresinoid, and particularly to the wire ends be ing bent laterallyasshown in 6, and due to the fact that the wire is reinforced and supported in position. by the molded resinoid, there is very little chanceof the wire being deformed or pulled out .of'shape or location duringuse of the chain. Thebar may be provided with threaded holes, and inthat case the resinoid may be of the iniusible and very hard type. it ispreferred, however, that the resinoid be slightly plastic so that thethreads may be cut by turning the pegs therein likean ordinary woodscrew. Since the steel peg is normally slightly tapered, the holes inthe bar may be tapered to the same extent, so that the parts will fitproperly, whereas it would not be possible to drill a tapered hole in awooden bar as heretofore made. The resinoid moreover is not afiected bymoisture and it keeps its shape under the standard conditions of use, aswell as having a far The linkage wire passing through the cross .bar maybe made in two separate pieces to form the oppositely arranged hooks,and the claims are tobe interpreted as covering this equivalentconstruction. For example, as shown in 8, a cross bar I having two setsof holes therein may have the hooks or eyelets 40 formed ofsubstantially U-shaped bodies having outwardly turned ends 4! and 42.The ends 42 may lie between two holes in the opposite rows. while theends 4| may be positioned between adjacent holes in the same row; or anyother suitable arrangement may be made for properly posi tioning theparts. It is preferable that both ends of the eyelet be embedded in thebar but one of the ends may be left free, if desired. The

eyelet may take any suitable shape provided an I end or portion thereofis embedded in the resinoid bar and interlocks sufficiently therewith toprevent its being pulled out of place.

It will also be understood, in view of the above explanation, that othermoldable materials may be substituted for the resinoid specified toexemplify the invention. For example, the cross bar may be made ofaluminum or various alloys used in die casting operations. It is,however, desirable that this substance of which the bar is made bemolded in place around the eyelet or hook which serves to fasten one barto another in the dobby chain. That is, the linkage wire or eyelet is tobe secured rigidly in position by the molding operation; hence it ispreformed and placed in the mold prior to the insertion of the moldablesubstance, whether metal or resinoid, that is employed to form the bar.

It will be appreciated that one may make many modifications in thisconstruction and that the above description is to be interpreted asillustrating the principlesof the invention, as well as specificapplications thereof, and not as limi tations except as defined by theappended claims.

I claim:

1. A dobby chain comprising a set of cross bars connected together bylinks, each bar being made of a molded plastic substance and havingtapered dobby peg holes therein arranged for receiving and beingthreaded by the pegs, and linkage members immovably secured in positionWithout interfering with the peg holes which are arranged for fasteningone bar in proper alignment with another.

2. A dobby chain comprising a set of cross bars connected together bylinks, each bar being made of a molded substance and having dobby pegholes therein and linkage eyelets immovably secured in position duringthe molding operation which are so shaped and located within the bar asto interlock therewith and prevent removal thereof.

3. A dobby chain comprising a set of cross bars and links connectingthem in alignment, each bar being formed of a molded substance andhaving tapered holes shaped to receive a tapered peg and link memberssecured immovably in place by the molded resinoid which are bent withinthe cross bar and so shaped as to prevent their removal.

4. A dobby chain comprising a cross bar made of a molded substancehaving peg holes formed therein and a linkage member embedded within thebar which has its central portion shaped to avoid passing closely to thepeg holes and its outer ends bent and embedded in the bar and formingclosed eyelets.

5. A dobby chain comprising a set of cross bars connected in alignmentby linkages, each bar being made of a molded substance and having dobbypeg holes therein, and linkage members immovably secured within thecross bar by the molding operation, each of which has a bent portionwithin the bar which prevents removal thereof and a hooked end embeddedin the bar and forming a closed eyelet.

6. A dobby chain comprising a cross barmade of a moldedsubstance havingrows of staggered dobby peg holes formed therein and a linkage memberhaving a central portion embedded in the bar without interfering withthe adjacent dobby peg holes and located at an angle to the direction oftractive force and having its opposite ends embedded in the bar andshaped to form closed eyelets.

'7. A dobby chain comprising a cross bar made of a molded substancehaving dobby peg holes formed therein and linkage members embeddedtherein at their central and end portions, each member being shaped toavoid the adjacent dobby peg holes and having its ends bent to formeyelets and further bent at an angle to the direction of tractive force.

8. A dobby chain comprising a set of linked cross bars made of a moldedsubstance which have tapered dobby peg holes therein and linkage membersembedded at their central and end portions in the bar in positions whichavoid intersecting the peg holes, each member being shaped to provide acentral bent portion located between the peg holes and an outer loopforming a linkage eyelet having its free end bent at an angle to thedirection of the tractive force involved in using the chain, so thatdeformation and removal of the linkage member is resisted.

9. A dobby chain comprising a cross bar made of a molded substancehaving dobby peg holes therein and separate opposed linkage eyeletshaving hooked ends embedded in and interlocking with the resinoid.

WARREN B. HARRIS.

